Semiconductor processing often involves etching, or otherwise forming openings over a substrate to expose desired substrate features. One type of opening which can be formed is a contact opening. Contact openings typically extend to conductive lines or diffusion regions with which electrical communication is desired. Such contact openings are then filled with conductive material and processing continues. In some instances, it is desirable to form openings, such as contact openings, to variable depths over a substrate. Such can be the case, for example, when certain lower elevation features are desired to be exposed without etching other higher elevation features.
It is generally desirable in semiconductor processing to minimize the number of processing steps which are utilized in forming integrated circuitry. Such can reduce the risk of a processing mistake adversely impacting the resultant circuitry.
This invention arose out of concerns associated with improving the manner in which integrated circuitry is formed. This invention also arose out of concerns associated with providing flexible processing methods which permit openings, and in particular contact openings, to be formed to different elevations over a substrate.